附件2-6：BM可引导光盘格式 use the standard INT 13 interface to place their software on the CD without regard to the media.The system's hard drive remains accessible because the stand alone CD may need some temporary disk storage. When the boot image is simply a"loader"or stand alone program,and NO EMULATION is desired,the drive numbers will be unaffected after the boot image is loaded.The specified number of sectors are loaded at the specified segment (usually 7C0),and then the BIOS jumps to the load address.The software can retrieve a pointer to its boot information by issuing INT 13,Function 4B,AL=1. If the Boot Indicator in Byte 0 is not an 88,the system accesses the next boot device,and the CD will now become the last drive in the user's drive sequence regardless of the image type.This allows software vendors to distribute data CD's which do not require device drivers for MS-DOS style accessing. 4.4 Boot Entry Selection If the CD has several boot entries,a default entry which boots a selection program may be provided as the Default/Initial catalog entry.This image will usually be a floppy image which loads a program that selects the proper boot image by examining the system configuration or questioning the user. Version 1.0 Copyright1994 Phoenix Technologies and IBM All Rights Reserved. Page 12附件2-6：IBM可引导光盘格式 Version 1.0 Copyright  1994 Phoenix Technologies and IBM All Rights Reserved. Page 12 use the standard INT 13 interface to place their software on the CD without regard to the media. The system’s hard drive remains accessible because the stand alone CD may need some temporary disk storage. When the boot image is simply a “loader” or stand alone program, and NO EMULATION is desired, the drive numbers will be unaffected after the boot image is loaded. The specified number of sectors are loaded at the specified segment (usually 7C0), and then the BIOS jumps to the load address. The software can retrieve a pointer to its boot information by issuing INT 13, Function 4B, AL=1. If the Boot Indicator in Byte 0 is not an 88, the system accesses the next boot device, and the CD will now become the last drive in the user’s drive sequence regardless of the image type. This allows software vendors to distribute data CD’s which do not require device drivers for MS-DOS style accessing. 4.4 4.4 Boot Boot Entry Entry Selection Selection Selection Selection If the CD has several boot entries, a default entry which boots a selection program may be provided as the Default/Initial catalog entry. This image will usually be a floppy image which loads a program that selects the proper boot image by examining the system configuration or questioning the user